Search NASA⌕ Search

SEARCH · Search NASA

Results for “visual tracking”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 631 records · Page 35
All sourcesNASA NTRSDOE OSTI
NASA NTRS2024

Evaluation of Intranasal Scopolamine for the Prevention of Wave Motion Induced Motion Sickness While Maintaining Performance on Operationally Relevant Tasks

Motion sickness represents one of the greatest clinical challenges impacting crew activities during and following g-transitions. Our overall goal is to characterize the effectiveness of motion sickness countermeasures during controlled laboratory experiments using capsule wave motion simulation and during field testing in operational environments. This laboratory study focused on prevention of motion sickness using intranasal scopolamine using a double-blinded repeated measures design in 30 subjects (19M, 11F). Intranasal scopolamine was provided by Defender Pharmaceuticals, Inc. (DPI-386 Nasal Gel, referred to as Inscop) self-administered by a nasal pump (Aptar Pharma) that delivers 0.4 mg dose (0.2 mg / nostril). During each session, subjects were exposed to complex wave motion on a six degree-of-freedom platform that included pitch, roll and heave at provocative stimulus frequencies (0.1-0.25 Hz) while seated in an illuminated cabin deprived of external visual cues. Motion sickness symptoms were compared across treatment and placebo control sessions counterbalanced across subjects and separated by at least one week. The time-to-motion sickness endpoint was based on severe malaise, defined as symptom score of ≥8 points using the Pensacola Diagnostic Index [1]. The bioavailability of scopolamine for each session was estimated from plasma concentrations obtained every 15 min[2]. Side effects during the treatment session were minimal, and performance was not impaired on a test battery including motion perception tracking, tablet-based eye-hand coordination and psychomotor vigilance testing. The plasma concentration remained near-peak levels throughout the 45 min motion sickness testing for most subjects. The percentile ranking on the Motion Sickness Susceptibility Questionnaire [MSSQ, 3]was moderately correlated with the motion sickness time-to-endpoint during the placebo control session (rho = –0.3, p=0.056). Seventeen subjects did not reach an endpoint during their placebo session and were eliminated from subsequent analysis. Another subject was excluded due to insufficient plasma concentration during the treatment session. For the remaining 12 subjects, the change in time-to-motion sickness endpoint between placebo and treatment sessions was moderately correlated with plasma concentration (rho =0.48, p = 0.056), improving on average 4.4 ± 18.4 min, mean ± std with Inscop versus placebo. Our results are consistent with previous findings that intranasal delivery of scopolamine can be effective at reducing motion sickness symptoms with minimal cognitive or sedative side effects. Future work is needed to optimize the delivery of Inscop for rescue (treatment) of symptoms following g-transitions as one of the key advantages of this formulation is self-administration in a suited environment. We will also explore how the combination of Inscop with non-pharmaceutical sensory aids, e.g., vibrotactile feedback of Earth vertical, may further mitigate motion sickness and improve task performance.

S J Wood↗
DOE OSTI2026

A framework and tool for designing cost-effective, resilient, and circular net-zero supply chains under uncertainty with an application to multilayer plastic films

While 55% of Fortune 500 companies have committed to achieving net-zero emissions and/or zero-waste operations by 2035, only 2% are currently on track, revealing a critical gap between ambition and action. Designing supply chains that reduce both emissions and waste is a complex non-intuitive, multi-objective challenge, compounded by the high costs of new technologies and the need for resilient, profitable solutions. This paper aims to address this challenge by presenting a generic framework and multi-objective optimization formulation for designing cost-effective, circular, and resilient supply chains under uncertainty, implemented through a user-friendly decision-support tool with intuitive data visualization capabilities, enabling communication of results to both technical and non-technical stakeholders. We demonstrate the application of this framework in the context of multilayer plastic films (barrier films), which are widely used in food packaging and composite materials. The model quantifies trade-offs across three objectives: minimizing global warming potential, maximizing circularity, and minimizing cost. A key contribution of this work is the explicit modeling of technological resilience, the ability of supply chains to maintain function under disruption. In the cost-minimization case, the resilience constraint makes the design approximately three times more expensive in the short-term metric, but shifts the system from relying on a single recovery pathway to a portfolio of four recovery pathways, improving the robustness of the optimization solution under uncertainty. Lastly, we introduce TranZero, a decision-support tool that integrates material flow analysis, hotspot identification, and optimization-based scenario planning to support net-zero and circularity decisions.

29 ENERGY PLANNING, POLICY, AND ECONOMY↗
NASA NTRS1985

Optical characteristics of lightning

A study of the optical characteristics of cloud-to-ground dischargers and how they compare with intracloud flashes was completed. Time resolved optical (7774A) and electric field-change waveforms were measured above clouds from a U2 airplane coincident with ground-based measurements of lightning. The optical pulse trains are studied for within and between flash variability. Specifically, for each flash researchers examine the 10, 50 (full width half maximum), and 90 percent pulse widths; the 10-10, 10-50, 10-90, and 10-peak percent amplitude rise times; the radiances (optical power densities); radiant energy densities; and pulse intervals. The optical pulse characteristics of first strokes, subsequent strokes, the intracloud components of cloud-to-ground flashes and intracloud flashes as viewed from above cloud are shown to exhibit very similar waveshapes, radiances and radiant energy densities. Descriptive statistics on these pulse categories were tabulated for 25 visually confirmed cloud-to-ground flashes (229 optical pulses) and 232 intracloud flashes (3126 optical pulses). A companion study of lightning observations above and below cloud in storms, storm complexes, and mesoscale convective systems has also been completed. Researchers compared the mapping of total lightning activity from above clouds with ground-based measurements and storm evolution. Although the total (IC + CG) lightning activity is the more representative indication of thunderstorm growth and decay, the ground strike data can be used to locate, diagnose, and track storm evolution in a number of instances.

Goodman, S. J.↗
NASA NTRS1990

In-simulator assessment of trade-offs arising from mixture of color cuing and monocular, binoptic, and stereopsis cuing information

The use of monochrome Helmet Mounted Display (HMD) systems is becoming prevalent in today's complex flight mission environment. These HMD systems can provide stereopsis cueing as an almost natural byproduct for binocular helmet systems of an additional image generation source is provided. The addition of color cueing capability is much more difficult. The application of stereopsis cueing to advanced HMD and heads-down flight display concepts has demonstrated gains in pilot situation awareness and improved task performance. To provide stereopsis, binocular HMD systems must trade some of the total field-of-view (FOV) available from their two monocular fields to obtain a partial overlap region. The visual field then provides a mixture of cues, with monocular regions on both peripheries, and, in the overlapped center, a binoptic (the same image to both eyes) or, if lateral disparity is introduced to produce two images, a stereo region. The goal of this research was to assess the trade-offs arising from the mixture of color cueing and monocular, biocular, and stereopsis cueing information in peripheral monitoring displays as encountered in HMD systems. The accompanying effect of stereopsis cueing in the foveal display of tracking information was also assessed.

Williams, Steven P.↗
DOE OSTI2026

String-Breaking Dynamics in Quantum Adiabatic and Diabatic Processes

Confinement prohibits isolation of color charges, e.g., quarks, in nature via a process called string breaking : the separation of two charges results in an increase in the energy of a color flux, visualized as a string, connecting those charges. Eventually, creating additional charges is energetically favored, hence breaking the string. Such a phenomenon can be probed in simpler models, including quantum spin chains, enabling enhanced understanding of string-breaking dynamics. A challenging task is to understand how string breaking occurs as time elapses, in an out-of-equilibrium setting. This work establishes the phenomenology of dynamical string breaking induced by a gradual increase of string tension over time. It, thus, goes beyond instantaneous quench processes and enables tracking the real-time evolution of strings in a more controlled setting. We focus on domain-wall confinement in a family of quantum Ising chains. Our results indicate that, for sufficiently short strings and slow evolution, string breaking can be described by the transition dynamics of a two-state quantum system akin to a Landau-Zener process. For longer strings, a more intricate spatiotemporal pattern emerges: the string breaks by forming a superposition of bubbles (domains of flipped spins of varying sizes), which involve highly excited states. We finally demonstrate that string breaking driven only by quantum fluctuations can be realized in the presence of sufficiently long-ranged interactions. This work holds immediate relevance for studying string breaking in quantum-simulation experiments.

Ising model↗
DOE OSTI2024

Utility-Scale Solar, 2024 Edition: Empirical Trends in Deployment, Technology, Cost, Performance, PPA Pricing, and Value in the United States [Slides]

Berkeley Lab’s “Utility-Scale Solar, 2024 Edition” presents analysis of empirical plant-level data from the U.S. fleet of ground-mounted photovoltaic (PV), PV+battery, and concentrating solar-thermal power (CSP) plants with capacities exceeding 5 MWAC (PV plants of 5 MWAC or less, including residential rooftop systems, are covered separately in Berkeley Lab’s companion annual report, Tracking the Sun). Key findings from this year’s report include: -18.5 GWAC of new utility-scale PV capacity came online in 2023, bringing cumulative installed capacity to more than 80.2 GWAC across 47 states. Installed costs continued to fall in 2023. Relative to 2022, capacity-weighted averages decreased by 8% to -$\$1.43$/WAC (or $\$1.08$/WDC). Costs, based on a 7.1 GWAC sample of 76 plants completed in 2023, have fallen by 75% (averaging 10% annually) since 2010. Plant-level capacity factors vary widely, from 6% to 36% (on an AC basis), with a sample median of 24%. -Levelized cost of energy (LCOE) of new 2023 projects increased slightly to $\$46$/MWh prior to the application of tax credits but continued to fall to $\$31$/MWh when accounting for federal incentives. PPA prices have largely followed the decline in solar’s LCOE over time, but newly signed longer-term PPA prices have increased since 2021, to an average of $\$35$/MWh (levelized, in 2023 dollars). -Solar’s average energy and capacity value (i.e., ability to offset costs of other power generation sources) across the U.S. was $\$45$/MWh in 2023. Solar’s average market value was lowest in CAISO ($\$27$/MWh), the market with the greatest solar generation share, and highest in ERCOT ($\$67$/MWh). -Newer solar projects had greater market value in 2023 than their generation costs, yielding $\$1.1$ billion in benefits. Projects built in 2022 delivered on average $\$15$/MWh more market value than their costs in 2023. -Solar’s combined value from wholesale electricity markets, public health and climate damage reduction were greater than generation costs and incentives, yielding $\$13.7$ billion in net benefits in 2023. We estimate U.S. health benefits of $\$24$/MWh and reduced global climate damages of $\$101$/MWh. -Adding battery storage is one way to increase the value of solar. Deployment of 52 new PV+battery hybrid plants set a record with 5.3 GW installed in 2023. Our public data file tracks metadata and PPA prices from more than 100 PV+battery hybrid projects that are already online or that have secured offtake arrangements. -Looking ahead, a massive pipeline of at least 1,085 GW of solar capacity dominates the nation’s interconnection queues at the end of 2023. Nearly 571 GW, or 53%, of that total was paired with a battery – in CAISO it was a staggering 98%. Historically only 10% of the requested solar capacity is built. -For more information, and to explore related interactive data visualizations, go to utilityscalesolar.lbl.gov.

14 SOLAR ENERGY↗
NASA NTRS2007

Comparison of Two Alternate Methods for Tracking Toe Clearance

Analyses of toe clearance during the swing phase of locomotion has often been utilized in determining a subject s propensity to trip while either walking or stepping over an obstacle. In the literature, toe clearance has been studied using a marker on the superior aspect of the second toe (rtoe), a marker on the lateral aspect of the fifth metatarsal head (mth5), or a virtual marker positioned at the anterior tip of the toe (vtoe). The purpose of this study was to compute toe clearance and associated parameters using a fifth metatarsal marker and a virtual toe marker, and compare the results with those of the standard toe marker. Subjects walked on a motorized treadmill at five different speeds while performing a visual acuity task at two separate target distances (ten 60-second trials). The minimum vertical height (TCl) was determined for each stride, along with its point of occurence in the gait cycle, and the angles of the foot and ankle at that time. A regression analysis was performed on the vtoe and mth5 results versus rtoe individually. For all TCl parameters, the mth5 marker did not correlate well with rtoe; the vtoe marker showed better agreement. Most importantly, the mth5 marker predicted a later occurence of TCl than rtoe and vtoe - thereby missing the most dangerous point in swing phase for a trip. From this analysis, the vtoe marker proved to be a better analog to rtoe than mth5, especially for determining a subject s propensity to trip.

Miller, Christopher A.↗
NASA NTRS2001

Dynamic and kinematic strategies for head movement control

This paper describes our analysis of the complex head-neck system using a combination of experimental and modeling approaches. Dynamical analysis of head movements and EMG activation elicited by perturbation of trunk position has examined functional contributions of biomechanically and neurally generated forces in lumped systems with greatly simplified kinematics. This has revealed that visual and voluntary control of neck muscles and the dynamic and static vestibulocollic and cervicocollic reflexes preferentially govern head-neck system state in different frequency domains. It also documents redundant control, which allows the system to compensate for lesions and creates a potential for substantial variability within and between subjects. Kinematic studies have indicated the existence of reciprocal and co-contraction strategies for voluntary force generation, of a vestibulocollic strategy for stabilizing the head during body perturbations and of at least two strategies for voluntary head tracking. Each strategy appears to be executed by a specific muscle synergy that is presumably optimized to efficiently meet the demands of the task.

Non-NASA Center↗
NASA NTRS2017

Analysis of Eye-Tracking Data During Conditions Conducive to Loss of Airplane State Awareness

In the constant drive to further the safety and efficiency of air travel, the complexity of avionics-related systems and of the procedures for interacting with them appear to be on an ever-increasing trend. While this growing complexity often yields productive results with respect to system capabilities and flight efficiency, it typically places a larger burden on pilots to manage increasing amounts of information and to understand intricate system designs. This can be problematic as too much information and/or ineffective provisions of information can potentially overwhelm and/or confuse pilots, and as a result, increase the likelihood of loss of airplane state awareness (ASA). One way to gain more insight into this issue is through experimentation using more objective measures. This study summarizes an analysis of eye-tracking data obtained during a high-fidelity flight simulation study that included most of the complexities of current flight decks, as well as several planned for the next generation air transportation system. Multiple analyses were performed to understand how the 22 participating airline pilots were observing ASA-related information provided during different stages of flights and in response to specific events within these stages. Also, study findings are compared to data presented in similar previous studies to assess trends or common themes regarding how airline crews apply visual attention in complex flight deck and operational environments.

Dill, Evan T.↗
NASA NTRSDate not supplied

Distributed Visual Sensing and Fusion for Advanced Air Mobility

Surveillance solutions for Advanced and Urban Air Mobility frameworks are a key factor to enable safe operations of highly automated aircraft in the civil airspace. To design solutions suitable for all types of aircraft, non-cooperative sensors can be used, though many challenges arise when the small dimensions of the vehicles and their proximity to the ground during low-altitude missions are considered. A distributed sensing concept can be efficiently applied to address these challenges by exploiting multiple sensors within a surveillance network. This paper proposes a strategy to fuse the information collected by three ground-fixed cameras within a network of multiple distributed sensors and is tested with during experimental flight tests. The solution exploits standalone tracking estimates of each camera within a fusion center that performs triangulation and three-dimensional tracking. This approach is tested in a scenario involving two small UAVs flying at low altitude. The paper deals with the challenges of associating the two objects from independent and unrelated tracks to achieve robust triangulation, which produces meter-level mean errors with respect to GNSS-based ground truth.

Federica Vitiello↗
NASA NTRS1994

Laboratory and in-flight experiments to evaluate 3-D audio display technology

Laboratory and in-flight experiments were conducted to evaluate 3-D audio display technology for cockpit applications. A 3-D audio display generator was developed which digitally encodes naturally occurring direction information onto any audio signal and presents the binaural sound over headphones. The acoustic image is stabilized for head movement by use of an electromagnetic head-tracking device. In the laboratory, a 3-D audio display generator was used to spatially separate competing speech messages to improve the intelligibility of each message. Up to a 25 percent improvement in intelligibility was measured for spatially separated speech at high ambient noise levels (115 dB SPL). During the in-flight experiments, pilots reported that spatial separation of speech communications provided a noticeable improvement in intelligibility. The use of 3-D audio for target acquisition was also investigated. In the laboratory, 3-D audio enabled the acquisition of visual targets in about two seconds average response time at 17 degrees accuracy. During the in-flight experiments, pilots correctly identified ground targets 50, 75, and 100 percent of the time at separation angles of 12, 20, and 35 degrees, respectively. In general, pilot performance in the field with the 3-D audio display generator was as expected, based on data from laboratory experiments.

Ericson, Mark↗
NASA NTRS2004

Advanced Infant Car Seat Would Increase Highway Safety

An advanced infant car seat has been proposed to increase highway safety by reducing the incidence of crying, fussy behavior, and other child-related distractions that divert an adult driver s attention from driving. In addition to a conventional infant car seat with safety restraints, the proposed advanced infant car seat would include a number of components and subsystems that would function together as a comprehensive infant-care system that would keep its occupant safe, comfortable, and entertained, and would enable the driver to monitor the baby without having to either stop the car or turn around to face the infant during driving. The system would include a vibrator with bulb switch to operate; the switch would double as a squeeze toy that would make its own specific sound. A music subsystem would include loudspeakers built into the seat plus digital and analog circuitry that would utilize plug-in memory modules to synthesize music or a variety of other sounds. The music subsystem would include a built-in sound generator that could synthesize white noise or a human heartbeat to calm the baby to sleep. A second bulb switch could be used to control the music subsystem and would double as a squeeze toy that would make a distinct sound. An anti-noise sound-suppression system would isolate the baby from potentially disturbing ambient external noises. This subsystem would include small microphones, placed near the baby s ears, to detect ambient noise. The outputs of the microphone would be amplified and fed to the loudspeakers at appropriate amplitude and in a phase opposite that of the detected ambient noise, such that the net ambient sound arriving at the baby s ears would be almost completely cancelled. A video-camera subsystem would enable the driver to monitor the baby visually while continuing to face forward. One or more portable miniature video cameras could be embedded in the side of the infant car seat (see figure) or in a flip-down handle. The outputs of the video cameras would be transmitted by radio or infrared to a portable, miniature receiver/video monitor unit that would be attached to the dashboard of the car. The video-camera subsystem can also be used within transmission/reception range when the seat was removed from the car. The system would include a biotelemetric and tracking subsystem, which would include a Global Positioning System receiver for measuring its location. This subsystem would transmit the location of the infant car seat (even if the seat were not in a car) along with such biometric data as the baby s heart rate, perspiration rate, urinary status, temperature, and rate of breathing. Upon detecting any anomalies in the biometric data, this subsystem would send a warning to a paging device installed in the car or carried by the driver, so that the driver could pull the car off the road to attend to the baby. A motion detector in this subsystem would send a warning if the infant car seat were to be moved or otherwise disturbed unexpectedly while the infant was seated in it: this warning function, in combination with the position- tracking function, could help in finding a baby who had been kidnapped with the seat. Removable rechargeable batteries would enable uninterrupted functioning of all parts of the system while transporting the baby to and from the car. The batteries could be recharged via the cigarette-lighter outlet in the car or by use of an external AC-powered charger.

Dabney, Richard↗
NASA NTRS2000

CaMKIIalpha 3' untranslated region-directed mRNA translocation in living neurons: visualization by GFP linkage

The CaMKIIalpha mRNA extends into distal hippocampal dendrites, and the 3' untranslated region (3'UTR) is sufficient to mediate this localization. We labeled the 3'UTR of the CaMKIIalpha mRNA in hippocampal cultures by using a green fluorescent protein (GFP)/MS2 bacteriophage tagging system. The CaMKIIalpha 3'UTR formed discrete granules throughout the dendrites of transfected cells. The identity of the fluorescent granules was verified by in situ hybridization. Over 30 min time periods these granules redistributed without a net increase in granule number; with depolarization there is a tendency toward increased numbers of granules in the dendrites. These observations suggest that finer time resolution of granule motility might reveal changes in the motility characteristics of granules after depolarization. So that motile granules could be tracked, shorter periods of observation were required. The movements of motile granules can be categorized as oscillatory, unidirectional anterograde, or unidirectional retrograde. Colocalization of CaMKIIalpha 3'UTR granules and synapses suggested that oscillatory movements allowed the granules to sample several local synapses. Neuronal depolarization increased the number of granules in the anterograde motile pool. Based on the time frame over which the granule number increased, the translocation of granules may serve to prepare the dendrite for mounting an adequate local translation response to future stimuli. Although the resident pool of granules can respond to signals that induce local translation, the number of granules in a dendrite might reflect its activation history.

NASA Discipline Neuroscience↗
NASA NTRS1993

Analysis of passive acoustic ranging of helicopters from the joint acoustic propagation experiment

For more than twenty years, personnel of the U.S.A.E. Waterways Experiment Station (WES) have been performing research dealing with the application of sensors for detection of military targets. The WES research has included the use of seismic, acoustic, magnetic, and other sensors to detect, track, and classify military ground targets. Most of the WES research has been oriented toward the employment of such sensors in a passive mode. Techniques for passive detection are of particular interest in the Army because of the advantages over active detection. Passive detection methods are not susceptible to interception, detection, jamming, or location of the source by the threat. A decided advantage for using acoustic and seismic sensors for detection in tactical situations is the non-line-of-sight capability; i.e., detection of low flying helicopters at long distances without visual contact. This study was conducted to analyze the passive acoustic ranging (PAR) concept using a more extensive data set from the Joint Acoustic Propagation Experiment (JAPE).

Carnes, Benny L.↗
NASA NTRS1977

Reliability measurement during software development

Measurement of software reliability was carried out during the development of data base software for a multi-sensor tracking system. Every run made during this project was scored as success or failure, and supporting data were collected on forms for further analysis. The failure ratio (number of failures per calendar interval divided by total number of runs) and failure rate (number of failures divided by CPU time for the interval) were found to be consistent measures, on a month-to-month basis as well as from module to module, and therefore considered valid indicators of reliability in this environment. Trend lines could be established from these measurements that provide good visualization of the progress on the job as a whole as well as on individual modules. Over one-half of the observed failures were due to factors associated with the specific run submission rather than with the code proper.

Hecht, H.↗
NASA NTRS1984

TAC BRAWLER - An application of engagement simulation modeling to simulator visual system display requirements for air combat maneuvering

The TAC BRAWLER air combat simulation models both the acquisition and use of visual information by the pilot. It was used to provide the designers of manned simulators for air-to-air combat with information regarding the training implications of display system resolution, inherent target contrast, field of view, and transport delay. Various display designs were simulated, and the resulting quantitative and qualitative differences in engagements were considered indicators of possible mistraining. Display resolution was found to alter combats primarily through its effect on detection ranges; the 'pixel averaging' contrast management technique was shown to largely compensate for this problem. Transport delay significantly degrades pilot tracking ability, but the training impact of the effect is unclear.

Kerchner, R. M.↗
NASA NTRS2010

Part-Task Simulation of Synthetic and Enhanced Vision Concepts for Lunar Landing

During Apollo, the constraints placed by the design of the Lunar Module (LM) window for crew visibility and landing trajectory were a major problem. Lunar landing trajectories were tailored to provide crew visibility using nearly 70 degrees look-down angle from the canted LM windows. Apollo landings were scheduled only at specific times and locations to provide optimal sunlight on the landing site. The complications of trajectory design and crew visibility are still a problem today. Practical vehicle designs for lunar lander missions using optimal or near-optimal fuel trajectories render the natural vision of the crew from windows inadequate for the approach and landing task. Further, the sun angles for the desirable landing areas in the lunar polar regions create visually powerful, season-long shadow effects. Fortunately, Synthetic and Enhanced Vision (S/EV) technologies, conceived and developed in the aviation domain, may provide solutions to this visibility problem and enable additional benefits for safer, more efficient lunar operations. Piloted simulation evaluations have been conducted to assess the handling qualities of the various lunar landing concepts, including the influence of cockpit displays and the informational data and formats. Evaluation pilots flew various landing scenarios with S/EV displays. For some of the evaluation trials, an eye glasses-mounted, monochrome monocular display, coupled with head tracking, was worn. The head-worn display scene consisted of S/EV fusion concepts. The results of this experiment showed that a head-worn system did not increase the pilot s workload when compared to using just the head-down displays. As expected, the head-worn system did not provide an increase in performance measures. Some pilots commented that the head-worn system provided greater situational awareness compared to just head-down displays.

Arthur, Jarvis J., III↗
NASA NTRS1999

High-Resolution Mapping of Lunar Crustal Magnetic Fields: Correlations with Albedo Markings of the Reiner Gamma Class

During the last eight months of the Lunar Prospector mission (December 1999-July 1999), the spacecraft was placed in a relatively low-altitude (15-30-km perapsis), near-polar orbit that allowed high-resolution mapping of crustal magnetic fields. We report here initial studies of the correlation of locally strong magnetic anomalies with unusual, swirl-like albedo markings of the Reiner Gamma class. Based on this correlation, which is known from earlier studies of Apollo subsatellite magnetometer data, it has been proposed that the swirls represent regions whose higher albedos have been preserved via deflection of the solar-wind ion bombardment by strong crustal fields. This model in turn depends on the hypothesis that solar-wind implanted H is at least one component of the process that optically matures exposed silicate surfaces in the inner solar system . Specifically, it is hypothesized that implanted H acts as an effective reducing agent to enhance the rate of production of nanophase metallic Fe particles from preexisting silicates during micrometeoroid impacts. According to the model, the curvilinear shapes of these albedo markings are caused, at least in part, by the geometry of ion deflections in a magnetic field. The improved resolution and coverage of the Prospector data allow more detailed mapping of the fields, especially on the lunar farside. This permits a more quantitative test of whether all albedo markings of this class are associated with strong local magnetic fields.Only if the latter condition is met can the solar-wind deflection hypothesis he valid. The basic procedure for mapping crustal magnetic fields using Lunar Prospector magnetometer data follows that developed for analysis of Apollo subsatellite magnetometer data. The specific mapping steps are (1) selection of mission time intervals suitable for mapping crustal fields; these are limited essentially either to times when the Moon is in a lobe of the geomagnetic tail or to times when the Moon is in the solar wind but the spacecraft is in the lunar wake; the data are transformed to a radial, east, and north coordinate system with measurements given as a function of spacecraft latitude, longitude, and altitude; (2) visual editing of individual orbit segments selected for minimal external field disturbances; (3) minimization of remaining low-frequency external fields for individual orbit data segments by quadratic detrending; and (4) two-dimensional filtering of individual orbit segments to produce a vector field map along the slightly curved surface defined by the spacecraft altitude; maps of the three field components (radial, east, and north), the field magnitude, and the spacecraft altitude are constructed. For data obtained at low to middle latitudes, the horizontal resolution of the field maps is limited by the orbit-track separation (about 30 km at the equator). Maps of the field magnitude have been constructed within limited selenographic regions based mainly on data acquired in March, April, and May of 1999. This was a time period when the orbit plane was nearly aligned with the Sun-Moon line so that field mapping was possible at times when the Moon was in the solar wind as well as when the Moon was in the geomagnetic tail. Most of the coverage is across the lunar farside. However, a shows an example of a field map produced from solar-wind wake data for a region including Reiner Gamm on western Oceanus Procellarum (location: 58.5W, 7.5N). The contour interval is 3 nT and the mean spacecraft altitude is 18 km to within the accuracy allowed by the resolution of the map (30 km or about 1 deg.); strong magnetic anomalies correlate closely with swirl locations. Individual orbit profiles (whose resolution along the orbit track is comparable to the spacecraft altitude of 18 km) also demonstrate a good correlation of field magnitude with surface albedo. In order to investigate the correlation of magnetic fields with the location of swirl features, we have reexamined available lunar imagery (Lunar Orbiter, Apollo, and Clementine) to identify and map swirl locations within regions where swirls have previously been mapped. In these images, swirls were distinguished from other high-albedo features such as crater rays by their curvilinear shapes and increased visibility in forward-scattered light. Digital maps of swirls identified by all available imagery were then superposed on maps of the field magnitude at the spacecraft altitude. Based upon analysis of these composite magnetic/geologic maps, we draw the preliminary conclusion that swirl features are associated with magnetic anomalies revealed by Lunar Prospector. Detailed maps of these swirl features are currently being constructed for the magnetically strong regions antipodal to the Imbrium, Serenitatis, and Crisium Basins. Additional information contained in the original,

Hood, L. L.↗